Folate, also known as vitamin B9, is a B vitamin that plays an important role in numerous bodily processes. This water-soluble nutrient is essential for cell growth and division, and for DNA and RNA synthesis and repair. Maintaining adequate folate levels supports overall health.
Medications That Interact with Folate
Certain medications can interfere with folate levels by disrupting absorption, metabolism, or increasing excretion. Antiepileptic drugs, such as phenytoin and carbamazepine, reduce folate absorption in the intestine and increase its breakdown, potentially leading to lower circulating folate. Methotrexate, used in chemotherapy and for autoimmune conditions like rheumatoid arthritis, inhibits the enzyme dihydrofolate reductase, which converts dietary folate into its active forms, impeding folate metabolism.
Sulfasalazine, prescribed for inflammatory bowel disease and rheumatoid arthritis, also impairs folate absorption by inhibiting the enzyme folate hydrolase, which releases folate from food. Some diuretics, particularly triamterene, act as weak folate antagonists, interfering with folate’s biological actions. These interferences can lead to a folate deficiency over time, potentially impacting cell division and DNA synthesis, or reducing medication effectiveness.
Dietary and Lifestyle Factors Affecting Folate
Dietary choices and lifestyle habits influence folate status. Chronic alcohol consumption impairs folate absorption from the digestive tract and increases its excretion, leading to depleted folate stores.
Folate metabolism is linked with other nutrients, notably vitamin B12. Vitamin B12 is required for the enzyme methionine synthase; without sufficient B12, folate can become “trapped” in an unusable form. Zinc also plays a role in folate absorption and metabolism, as zinc deficiency can hinder folate release from food proteins. Gastrointestinal conditions causing malabsorption, such as celiac disease or Crohn’s disease, can reduce dietary folate uptake.
Genetic Variations and Folate
Genetic predispositions can also influence how the body processes folate, with variations in the MTHFR gene being a recognized example. The MTHFR gene provides instructions for creating an enzyme called methylenetetrahydrofolate reductase. This enzyme is responsible for converting 5,10-methylenetetrahydrofolate into 5-methyltetrahydrofolate, which is the primary active form of folate (L-methylfolate) used by the body for various metabolic processes, including DNA synthesis and repair.
Variations in the MTHFR gene, such as the C677T and A1298C polymorphisms, can reduce the efficiency of this enzyme. For individuals with these variations, the conversion of dietary folate into its active form may be less efficient, potentially resulting in lower levels of active folate available to cells. This genetic influence highlights a predisposition in how an individual metabolizes folate, rather than indicating a disease state.